But it's from Italy, Spain or Greece, and in my efforts to buy less from overseas and reduce my food miles, it just wouldn't do. Heck, I'm far from perfect in that endeavour; I still buy Spanish tomatoes in the winter when I feel the need, asparagus from Peru when I crave it, oranges from goodness-knows-where, and the occasional avocado, but I try to keep these things to a minimum, and cooking oil is something I use every single day. So about a year ago I gave up olive oil completely, in favour of cold-pressed British rapeseed oil - a truly British product grown here for centuries, with an impressive nutritional profile, a pleasant floral flavour well-suited to cooking or raw use, and a high smoke point making it suitable for all types of cooking.
Photograph by David Castor, via Wikimedia Commons
So imagine my surprise and horror when an online acquaintance told me rapeseed oil was terribly bad for me and should be avoided by the health-conscious individual at all costs!
A few minutes of internet research showed that she wasn't alone - it appears a great many people believe rapeseed oil (or Canola oil across the pond) is dangerous stuff. But I quickly noticed virtually all the information cited on the subject of its dangers was from just two articles; one derived from a book by a certain John Thomas and the other a viral email that did the rounds years ago, which borrows heavily from John Thomas' theories. These articles have been reproduced over and over again on blogs and websites - a Google search suggests some 6000 times - despite being packed with misinformation, misquotation, innuendo and lies, and widely discredited (see here, here or here)! So I want to set the record straight here. And unlike the anti-rapeseed articles, I will make all my sources available via links, so you can check it out for yourself and make up your own mind.
The Myths About Rapeseed Oil
So for what reasons do some people think rapeseed oil is bad news?
Canola is not the name of a natural plant.
No, but it is a natural plant. Canola was a trade name derived from the words CANadian Oil, Low Acid. Rapeseed oil was originally grown for industrial purposes and was not very palatable because of its high levels of bitter erucic acid and glucosinolates, but in the 70s, agricultural scientists in Canada developed a low acid, disease- and drought- resistant cultivar which made an excellent and cheap cooking oil. In Canada, much of the Canola grown is genetically modified to be resistant to herbicides. Here in the UK, it has been bred naturally to achieve the same low-acid properties, just as we have cultivated and domesticated pretty much every other food crop we grow to reach its maximum commercial potential. Canola is now a generic name given to rapeseed oils up and down America. Here, we just call it rapeseed oil.
Rape is part of the mustard family. It's the most toxic of all food-oil plants. Insects will not eat it; it is deadly poisonous.
Rape is indeed in the mustard family (usually called brassicas), along with such nutritious and common edibles as, well, mustard, cabbage, broccoli, cauliflower, turnips, swedes, brussels sprouts, kale, radishes, horseradish, pak choi, rocket and cress. Although eating the wrong parts of a few species of wild mustards might upset your stomach, it does not follow that rape is toxic. Rape stems and leaves have long been used as a food in parts of Asia. Insects do eat rapeseed plants; flea beetles and cabbage moths are a particular problem, as with most brassicas.
Rapeseed oil is used in insecticides.
Any gardener who knows his stuff will know that many oils can be, and are, used as insecticides. A spray of oil easily blocks the spiracles (air holes) which allow insects to breathe, and they suffocate.
Rapeseed oil is an industrial oil, used as lubricant, fuel, soap and even in making plastics.
The author had obviously forgotten that olive oil was used as lamp oil for millenia and makes excellent soap, and that flax oil has long been used in paint, sealants and linoleum. They obviously didn't realise that sunflower, palm and castor oil have all been used widely as lubricants, and had never heard that Rudolf Diesel designed his first engines to run on peanut oil, nor that Henry Ford's first automobiles were actually made from hemp and soybean, two more highly nutritious food oils which also make excellent plastics.
Rape oil is strongly related to symptoms of emphysema, respiratory distress, anemia, constipation, irritability and blindness in animals and humans. Also increased risk of heart disease, low birth weight, disruption of the nervous system and cancer. It inhibits proper metabolism of foods, prohibits normal enzyme function and suppresses the immune system. In the blood, it causes red blood cells to stick together in clumps and congests blood flow.
No sources are given, and no evidence is available. Most of these claims appear to come from the book 'Young Again: How to Reverse the Aging Process' by John Thomas, in which the author makes many unusual claims which are completely unsupported. He uses no citations or scientific references, and in fact eschews science, calling the scientific mind 'muddled'. Some anti-rapeseed articles cite the Encyclopedia Britannica as saying rape is toxic. The online version does not make this claim, but clearly notes that it is a popular food crop.
It contains unhealthy trans fatty acids.
Fats become trans fats when they are processed with hydrogen to make them solid, stable and increase their shelf life. It is true that a refined and processed canola oil may contain small amounts of trans fats - as any refined and processed oil may. Trans fats are legally limited to just 2% in Canada and banned in an increasing number of cities and countries. No cold-pressed oil contains trans fats. Some anti-rapeseed articles claim that the oil must be heavily processed to get rid of its strong odour, colour and flavour. Any fan of British cold-pressed oil, with its rich golden colour and peppery floral flavour, will disagree.
Feeding rapeseed oil to livestock caused mad cow disease.
There is no evidence for this and no sources are given. It was rapeseed meal with the oil pressed out, not the oil itself, which was used as animal feed. Here in the UK, rapeseed meal is still used as nutritious animal feed and fish food, but there is no longer any CJD problem.
Rapeseed oil was the source of the chemical warfare agent 'mustard gas'.
This is just plain falsehood. Mustard gas is made from chemicals in a laboratory; commonly by treating sulfur dichloride (chlorinated sulfur) with ethylene. (Ethylene serves as a plant hormone in all plants, but has no special connection to mustard or its relatives.) The name simply came from its yellow colour and pungent mustard-like smell.
When rapeseed oil was fed to rats, they developed fatty degeneration of heart, kidney, adrenals, and thyroid gland. The fatty deposits disappeared when the oil was withdrawn from their diets but scarring remained.
The natural diet of a rat is grains and other plant matter. Is it any wonder that feeding them high levels of fats caused health problems commonly associated with consuming high levels of fats?
Rapeseed oil contains VLCFAs which can cause a rare fatal degenerative disease called adrenoleukodystrophy.
Adrenoleukodystrophy is an inherited disease which causes a disastrous build-up of fatty acids in the blood; not because sufferers consume too many VLCFAs (very long chain fatty acids) but because they simply cannot process those they do consume. The VLCFA present in rapeseed oil is erucic acid - the very acid that was bred out of rape cultivars (down to a maximum 2%, usually less) in order to make the product palatable. The source cited for this little claim (Fats That Heal, Fats That Kill, by Udo Erasmus) is severely misquoted; in fact the author actually goes on to describe how erucic acid has been used to normalise fatty acid levels and treat this very disease.
Rapeseed oil is a penetrating oil which leaves a stain on fabric that won't wash out.
Maybe I'm doing my laundry wrong, but I've never been able to get olive oil or sunflower oil spots out of clothes either... This does not make it toxic!
Rapeseed oil causes lung cancer.
Any oil heated past its smoke releases carcinogenic free radicals. No cooking oil should be heated above its smoke point, nor reheated so many times that its smoke point is significantly lowered through deterioration.
The Truth About Rapeseed Oil
Cold-pressed rapeseed oil is a healthy, natural, low impact food with an erucic acid level of around 1%. It contains only 6% saturated fat - that's half as much as olive oil - and has up to 11 times more essential omega 3 fatty acid and much less omega 6 than olive oil, giving it an essential fatty acid balance better suited to human consumption than any other oil (not enough omega 3 or too much omega 6, which is common, make us prone to inflammatory conditions and blood problems). Rapeseed oil provides lots of antioxidant vitamin E (though sunflower oil trumps it), is stable for up to a year, and has one of the highest smokepoints of any cooking oil, making it suitable for all kinds of cooking. (Source, source)
In short, rapeseed is the most heart-healthy oil, suitable for all culinary uses and with a far lower environmental impact than foreign oils.
Let me make a couple of disclaimers. First, processed oil is a different creature from cold-pressed, and the sterilising, deodorising, degumming, bleaching and chemical treatment of any processed oil will increase its bad fats and decrease its micro-nutrient content. I do not recommend processed or refined oils, or generic vegetable oil which is usually full of low-grade and refined oils. Second, Canadian/US Canola is (largely, though not exclusively) genetically modified and I do not support this. Time is showing that GM/GE crops give lower yields and pose other risks, and multinational GMO agribusiness Monsanto is very scary indeed, threatening farmers and crops all across America and Canada - watch this video or read this or browse here. We need to fight back against GM foods and I do not recommend GM Canola oil. Thankfully, GM crops are not grown in the UK.
As long as it's cold-pressed and British, rapeseed is the oil for me.
Photograph by Prazak, via Wikimedia Commons
A Quick Lesson in Fats (more here)
Cholesterol is a substance made in the body (and consumed in animal products) and essential to cell structure, hormones and vitamin D production. Cholesterol also moves fat around the body. There are two main types of cholesterol, with which we are concerned here:
Low-Density Lipoproteins (LDL cholesterol) are manufactured by the liver to carry cholesterol to the body’s cells and tissues. When there are too many, LDLs form deposits on the walls of arteries and elsewhere, and increase your risk of heart disease.
High-Density Lipoproteins (HDL cholesterol) pick up and carry excess cholesterol from artery walls and bring it back to the liver for processing and removal. HDLs decrease your risk of heart disease.
All fat has the same number of calories per gram (9) and will make you fat if you eat too much, but fat is an essential nutrient for our brains and nervous systems, not to mention joints, skin and hair. We must all eat fat, but the type of fat we choose can make a big difference to our health. Dietary fat is made up of fatty acids, which are grouped into three main types:
Saturated fats increase bad (LDL) cholesterol. They are usually solid at room temperature. Examples are butter, cheese, animal fat, coconut and palm oil.
Monounsaturated fats decrease bad (LDL) cholesterol but maintain your good (HDL) cholesterol. They are liquid at room temperature. Foods high in monounsaturated fats are olives, avocadoes and many nuts.
Polyunsaturated fats decrease your good (HDL) and bad (LDL) cholesterol. They are liquid or soft at room temperature. Sources include corn oil, soybean products, many seeds, and oily fish.
Trans fats are man-made; they are unsaturated fats which have undergone processing (hydrogenation) to make them more solid (as in many margarines), or just to increase their shelf life and make them more stable (this is partial hydrogenation). They not only increase bad (LDL) cholesterol, but they reduce the good stuff (HDL) and have been reported to cause a number of side effects too. They occur almost exclusively in processed foods (small amounts also occur naturally in some animal products) and are the unhealthiest fats of all - in fact many countries are moving towards banning them. Unsaturated cooking oils (such as rapeseed) can break down and turn to trans fats when heated in cooking, but in a domestic environment under normal conditions this risk is negligible, unless your oil is already oxidised by age, air/light/heat exposure, repeated use or overheating past its burn/smoke point.
Thank you to Hill Farm Oils and Yellow Fields Oil for providing information for this article.